Physics · 2022
JEE Main · 29 July 2022, Shift 1 · Q42
Two metallic wires of identical dimensions are connected in series. If σ_1 and σ_2 are the conductivities of the these wires respectively, the…
Two metallic wires of identical dimensions are connected in series. If $\displaystyle \sigma_1$ and $\displaystyle \sigma_2$ are the conductivities of the these wires respectively, the effective conductivity of the combination is :
Official answer
(2)
$\displaystyle \frac{2 \sigma_1 \sigma_2}{\sigma_1+\sigma_2}$
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JEE Main 2022 Physics question, with the answer from NTA’s final answer key. Where our answers come from.